Here is my code: it contains a button named as button1A and when I click on it, It opens a list named as list1. How can I put a code for my another button named as button2A which open a list as List2.

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.View;
import android.view.View.OnClickListener;

import android.widget.Button;

public class Tab_1st extends Activity {

Button button1A;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.tablayout1);

    addListenerOnButton();

}

public void addListenerOnButton() {

    button1A = (Button) findViewById(R.id.button1A);

    button1A.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

            Intent a1 = new Intent(v.getContext(), List1.class);
            startActivity(a1);

        }
    });

}

}

Change your addListenerOnButton method using switch-case to minimize code and add single OnClickListener listener to multiple button as :

    public void addListenerOnButton() {

        button1A = (Button) findViewById(R.id.button1A);
        button1A.setOnClickListener(clicklistener);
        // add OnClickListener to second Button
        button1B = (Button) findViewById(R.id.button1B);
        button1B.setOnClickListener(clicklistener);
    OnClickListener clicklistener = new View.OnClickListener() {
     @Override
      public void onClick(View v) {
        switch(v.getId()){

          case R.id.button1A:
                    // start second List Activity
               Intent a1 = new Intent(v.getContext(), List1.class);
               startActivity(a1);
               break;

          case R.id.button2A:
                     // start second List Activity
               Intent a2 = new Intent(v.getContext(), List2.class);
               startActivity(a2);
               break;

        }
       }
     };
   }

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